One effect of climate change is to heat the soil. In areas with permafrost, this warming process encourages the activity of microorganisms (bacteria and fungi) to breakdown dead parts of the plant matter held in permafrost. For this reason, scientists are studying what happens to the decomposition of organic material as the climate gets warmer.
Permafrost refers to soil, rock or sediment that is frozen over time. It exists trapped beneath a layer of soil, rock or sediment, which freezes and thaws. Some examples can be thousands of years old.
Through global warming, thawing permafrost has significant effects on surfaces governing hydrology and energy and moisture balance. Moreover, ecosystem diversity is impacted by increasing air temperatures. A concern among many environmentalists is that as a result of climate change, permafrost is at risk of melting, releasing the stored carbon in the form of carbon dioxide and methane, which are powerful heat-trapping gases. However, the situation may be a little more complex.
In a statement, one of the lead investigators, Johannes Rousk notes: “As the Arctic region becomes warmer, more shrubs start to grow, rather than moss.” The implication here is that shrubs are harder for microbes to decompose, especially those parts of the plant that are considered higher in sugars and therefore ‘nutrient rich.’
According to Rousk this effect has been overlooked in climate change models, especially in relation to levels of carbon in the soil. It is possible that the effect will help to counteract some of the effects of climate change, through lowering the rate of global warming. Further research, however, is needed to support this assertion. There may, for instance, be other effects such as on the rate of tundra methane release.
The research was undertaken at Lund University in Sweden, and the findings are published in the journal Global Change Biology. The research paper is titled “Microbial control of soil organic matter mineralisation responses to labile carbon in subarctic climate change treatments.”
The researchers provide a more detailed explanation in the following video:
